Vibrio parahaemolyticusのゲノム配列:V choleraeの病原性メカニズムとは異なる病原性メカニズム
Kozo Makino1, Kenshiro Oshima, Ken Kurokawa
1Department of Molecular Microbiology, Osaka University, Osaka, Japan.
Lancet (London, England)
|March 7, 2003
まとめ
Vibrio parahaemolyticusは胃腸炎を引き起こし,V. cholerae.とは異なり,III型分泌システム (TTSS) の遺伝子を有しています. このゲノム差異は,これらの関連細菌の間の異なる感染メカニズムと臨床症状を説明します.
科学分野:
- 微生物学 微生物学とは
- ゲノミクスゲノミクスとは
- 感染症 感染症は感染症です.
背景:
- Vibrio parahaemolyticusは,世界的な食物媒介性胃腸炎の原因となるグラム陰性海洋細菌です.
- V. parahaemolyticusの特定の血清型がパンデミックを引き起こしており,この生物はVibrio choleraeと密接に関連しています.
研究 の 目的:
- 臨床的なV. parahaemolyticus株の全ゲノム配列を決定する.
- V. parahaemolyticusのゲノムとV. choleraeのゲノムを比較して,遺伝子の違いを特定する.
- V. parahaemolyticus.の独特の病原性における特定の遺伝因子の役割を調査する.
主な方法:
- V. parahaemolyticus株RIMD2210633のホールゲノムシーケンシングは,ショットガンシーケンシングを用いて行われました.
- GamblerおよびGlimmerプログラムを使用してコード配列の識別.
- MUMmerを使ってV. choleraeとの比較ゲノム分析.
主要な成果:
- V. parahaemolyticusのゲノムは,4,832の遺伝子を持つ2つの円形の染色体 (3,288,558 bpと1,877,212 bp) を含む.
- V. parahaemolyticusとV. choleraeの染色体間で重要なゲノム再編成が観察されました.
- タイプIII分泌システム (TTSS) をコードする遺伝子はV. parahaemolyticusで特定されたが,V. cholerae.には存在しない.
結論:
- タイプIII分泌システム (TTSS) は,胃腸炎を引き起こす細菌における重要な毒性因子である.
- V. parahaemolyticusとV. choleraeは,異なる感染戦略を採用しています.
- V. parahaemolyticusのTTSSの存在は,V. choleraeの非炎症性下痢とV. choleraeの非炎症性下痢を区別して,その炎症性下痢と全身感染の可能性を説明しています.
関連する概念動画
01:25Cholera
Cholera is an acute gastrointestinal disease caused by the Gram-negative bacterium Vibrio cholerae. It is transmitted primarily via the fecal-oral route through the ingestion of contaminated water or food.Vibrio cholerae is a motile, Gram-negative bacterium of the family Vibrionaceae, primarily associated with waterborne outbreaks in areas with inadequate sanitation. Although over 200 serogroups of V. cholerae exist, only O1 and O139 are responsible for epidemic cholera. The O1 serogroup,...
01:28Regulation of Bacterial Virulence
Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...
01:18Bacterial Gastroenteritis
Bacterial gastroenteritis, characterized by diarrhea, abdominal cramps, and vomiting, is often caused by ingestion of contaminated food or water and is frequently associated with pathogenic Escherichia coli strains. These microbes exploit two principal mechanisms to inflict disease.Shiga toxin–producing E. coli, also referred to as STEC—notably O157:H7—release Shiga toxins that target ribosomes, blocking protein synthesis. The B subunit of the toxin binds the host glycolipid receptor...
01:20Determinants of Bacterial Pathogenicity and Virulence
Pathogenic bacteria employ a variety of strategies to establish infections, including the secretion of extracellular enzymes that act as potent virulence factors. These enzymes facilitate bacterial colonization of host tissues and help evade immune surveillance. By targeting structural components of host tissues and interfering with immune mechanisms, these enzymes play a pivotal role in disease progression.Extracellular Enzymes Facilitating Tissue Invasion: Several bacterial pathogens secrete...
01:23Bacteriophages of the Human Virome
Bacteriophages are found throughout the human body. They may even outnumber eukaryotic viruses, forming an important and dynamic component of the human virome. Indeed, phages represent the most abundant viral entities, with densities in the gut reaching up to 10⁹ particles per gram of fecal matter, and many belonging to orders such as Caudovirales and Microviridae, while a substantial proportion remains unclassified as viral “dark matter.”Lysogeny and Genetic ExchangeIn the gut, bacteriophages...
01:20Viral Replication: Lytic Cycle
Bacteriophages, or phages, are viruses that specifically infect bacteria. Among them, T-even bacteriophages, such as T4, exhibit a well-characterized lytic replication cycle in Escherichia coli (E. coli). This process ensures the rapid proliferation of the virus while ultimately leading to the destruction of the bacterial host.Attachment and DNA InjectionThe infection process begins with the recognition and binding of the T4 phage to the E. coli cell surface. Tail fibers of the phage...